Time-delay relay circuits



G. E. BRODE sept. 4, 1951 TIME DELAY RELAY CIRCUITS Filed Nov. 1o,194'.'

INVENToR. 650x765 f. 5,9005

Patented Sept. 4, 1951 2,566,309 y rma-DELAY RELAY cmcurrs George E.Brodo, Newark, N. J., assignor to Fed- Yeral Telephone and RadioCorporation, New

York, N. Y., a corporation of Delaware Application November 10, 1947,Serial No. 784,985

2 Claims. (Cl. 175-320) l My invention relates to time delay relaycircuits and is particularly directed to circuits for accuratelymeasuring a predetermined time interval after an initiating electricpulse.

2 normally open contacts 5, the winding and contacts being electricallyconnected in series. Relav 6 comprises winding l and the normally closedcontacts 8. With contacts 5 in series with There are numerousapplications of time delay 5 winding 4, contacts 5 lock-up once windingI circuits. In industrial counting mechanisms, for is energized.Hence,switch Il is placed across example, a power relay-must be actuateda given the contacts I. time after actual counting by a phototube or aThe rst and instantaneous result of the clotrigger ilnger. Heretofore,the necessary time sure of contacts 5, is the ignition of a dischargedelay has been obtained by ordinary slow rei in the gaseous dischargedevice 9, the anodelease relays using direct current power supplies.Cathode Space being COIIHCCted aCrDSS the volt- There is not only nocontrol over the length age SO'JI'C@ 2 through Contacts 5. 'I'he controlof the delay period, but it is oftenv inconvenient. 0r starter electrodel0 may be a grid or a pointed to obtain the direct current. Thecopper-oxide igniiing eleCtIOde and the CathOde ll may be type rectifieris undesirable because of vsize and iof the cold type such as a coldoxide coated memtemperature limitations while vacuum tube recbei 01' aD001 of mercury. Anode potential is tiers employing hot cathodes are notsuitable applied to the starter electrode Ill through rebecause of thetime delay involved in raising the sistor I2. The discharge current willcause a cathode to operating temperature and because, considerablevoltage drop across cathode resistor for intermittent operation, it iseostly to maini I3. the half-wave pulses being smoothed as detain acathode hot. Alternating current-oper- Sired with condenser Il. atedrelays have obvious advantages. Condenser I5 and resistor I6 areconnected The general object of my invention is an imin series andacross the cathode resistor, the proved time deiey circuit, timeconstant of this network being adjusted to A more specic object of myinvention is a any desiredvalue by adjustment of the values Iinie delaynii-cuit which is simple in consti-unof the condenser I5 and/or theresistor I6. It tion, adjustable as to time delay, and is ecowill morefully appear hereinafter that the time nomical and reliable inoperation. constant of this capacity-resistance network A stiii morespeciiie object of my invention easily predetermines the delay time ofthe system. is a time delay circuit that 1s entirely operable 30 TheSecond gaseous discharge device I1 is also on alternating current.Connected across the source 2 through contacts The Scope of my inventionis particularly de- 5. Ignition of a discharge in tube II, and enerilnedin the appended claims'and exemplary lemvSizliiorl 0f the Winding 7.must, however, await bodiments thereof are described in the followingthe Proper potential on the control electrode la, specification vandShdwnA in Vthe accompanying The condenser I5 is connected directlyacross drawing in which the grid-cathode of tube I l, so that thisignitpig'e i and 3 are circuit diagrams of two nf ing potential isdetermined by the charge of the seid embodiments, and condenser I5.Hence, ignition of a discharge Ngs 2 and 4 are time-Sequence graphs ofim.. in tube 1 S delayed fOr an interval Of portant voltages of thecircuits of Figs. 1 and 3, 40 determined by the timi! Constant 0f theCapacityie5pectiveiy, I resistance network Iii-I6. Energization of wind-AAt il is shown e pu5h bntt0n switch which is ing, 'l opens the normallyclosed rcontacts 8 of arbitrarily chosen for illustration here toexrelay 6 Which in turn deenel'EiZeS the Winding emplify any switch orkey that serves to momen- 4. allOWiIlg Contacts 5 t0 fall Opentarllyclose a circuit, the lgsure of which is to A Utilization Cll'cllllL'OlCircuit t0 be cOVIltI'Olled, be followed by the actuation of certainrelays may comprise l.` relay Winding in any Portion 0f in predeterminedtime sequence and at predetermined intervals. Switch I may. for example,comprise the contacts oi.' a photoelectric-actuated relay of anindustrial counter, and the sequential operations to follow may includemotor start-stop switching. At I is represented'a voltage source whichaccording to my invention is alternating current. At 3 is anelectromagnetic relay of conventional design with winding I and thecircuits shown which carries current only during the delay period, orconveniently, aux- A iliary contacts may be operated by the armature ofeither relay 3 or 8. In Fig. 1, for example. contacts I9 in the circuitto be controlled are operated by the armature of relay 3.- The contactsI9 may be normally open or normally closed. as desired.

56 The sequence o! operations oi.' the circuits of Fig. 1 may bediagrammed as Fig. 2. Switch I is at least momentarily closed and relayl locked up. Contacts I9 close, assuming these contacts are normallyopen. A discharge in tube 9 is immediately initiated and condenser I5starts charging. After a. predetermined time grid I8 ignites tube I'I,whereupon Winding 'I opens contacts 8. The then deenergized winding 4releases and opens contacts 5 and I9. That is, contacts I9 operate atthe beginning and at the end oi this sequence, the time interval beingmeasured by the size or capacity of condenser I 5/or the ohmic value ofresistor I6, either of rwhich is easily adjusted. The samesequenceiollows each time switch I is closed.

The circuits of Fig. `3 are in all respects the same as the circuits ofFig. 1but with the addie commercial alternating current, -requires notion of relay windings and 2l specically for I operating contacts I9.The contacts I9, oi the circuit to be controlled, are here mechanicallyconnected withl a common armature for the two windings 2'0 and 2| sothat energization of either winding will serve to actuate contacts I9.The l windings 20 and 2| may he placed on Separate or on a common coreas desired. Winding 20 is connected across the voltage source 2 back ofswitch I so that at the instant switch I is closed, the armature ofcontacts I9 pulls up. Thev other winding 2| is connected in series withresistor 22 and the back and `normally closed contacts A23 of relay 3across condenser'IS. Thus, with contacts '23 closed, and with condenserI5 charged, winding 2I may also energize and pull up the armature ofcontact I9.

In operation, closure of switch I locks up rel lay 3 as in Fig. 1,andthe sequence of operations graphically represented in Fig. 4 follows.Contacts 5 close and contacts 23 open. In addition to initiation of adischarge in tube 9, winding 20 is immediately energized and condenserI5 startscharging. After a predetermined time', condenser I5 is chargedto asuilicient potential to ignite tube I1, whereupon winding 1 openscontact B, deencrgizing winding 4 andreleasing its armature.V Ascontacts -5 open, contacts 23 close, connecting the now chargedcondenser I5 across the winding 2|, and transferring the holdstand-by oridling current, is easily adjustable,

is simple and inexpensive in construction, and

is reliable in operation.

' I claim:

1. Altime delay circuit comprising a voltage source, a lock up relay,said relay having at least one winding connected across said source, atleast one pair of contacts controlled by said relay, said winding beingin series with said pair of contacts, said source connectedl to saidrelay for holding closed said contacts, a normally open switch acrosssaid contacts of said relay, rst and second discharge tubes .connectedin parallel across said source through said pair of contacts, i

a resistorA in the cathode circuit of said rst discharge tube, acapacity-resistance network coning force on the arma-ture and contact I9from winding 20 to winding 2|. It is assumed in this While in someapplications of my time delay circuit, an overlap of the energzationpenected in` series across said cathode resistor, a vsecond-relay in theanode circuit of said second tube, normally closed contactsassociatedwith saidl second relay, said normally closed contacts .beingconnected in series with the winding-of said lookup relay. j

l 2. A time delay circuit according to claim 1 and further comprisingthird and fourth relay windings, ,andal further slet of contactscontrolled by saidfirst mentioned winding, said third winding beingconnected across said source, said fourth wlndingbeing connected inseries with said capacity-resistancenetwork, said'third and fourth.windings being alternately energized correspondingly with theenergization and deenergization of said iirst mentioned winding.

, GEORGE E. BRODE.

REFERENCESv CITED The following references are of record in the le ofthis patent:

